If encountered and tried to fix Nokia C3 such as No audio sound can be heard over the earpiece speaker, this solution may help as a guide to solved the problem.
After ensuring that earpiece speaker is working okay or already tried to
replace a new one, but still no sounds can be heard over it, just check
or replace the components showed on the solution below.
Nokia C3 Earpiece Speaker No sound problem solution
Those components are composed of a filter coil and an ESD resistors
which were located at the top of the PCB board near the LCD pin
connector. Hope this help repair Nokia C3 earpiece speaker problem.